If any human being earnestly desire to push on to new discoveries instead of just retaining and using the old; to win victories over Nature as a worker rather than over hostile critics as a disputant; to attain, in fact, clear and demonstrative knowlegde instead of attractive and probable theory; we invite him as a true son of Science to join our ranks.
The rising unto place is laborious, and by pains men come to greater pains; and it is sometimes base, and by indignities men come to dignities. The standing is slippery, and the regress is either a downfall, or at least an eclipse.
The human understanding is moved by those things most which strike and enter the mind simultaneously and suddenly, and so fill the imagination; and then it feigns and supposes all other things to be somehow, though it cannot see how, similar to those few things by which it is surrounded.
There was a young man in Rome that was very like Augustus Caesar; Augustus took knowledge of it and sent for the man, and asked him "Was your mother never at Rome?" He answered "No Sir; but my father was."
Man, being the servant and interpreter of Nature, can do and understand so much and so much only as he has observed in fact or thought of the course of nature; beyond this he neither knows anything nor can do anything.